Therapeutic vaccine for treatment of diabetes type 1 in children, application of the cell sorter and the method of multiplying treg cells to produce therapeutic vaccine for treatment of diabetes type 1

ABSTRACT

The gist of the invention consists in the therapeutic vaccine for treatment of diabetes type 1 in children, which contains
         Treg cells CD3(+)CD4(+)CD25(high)CD127(−). Claimed too is the cell sorter used to produce the vaccine and the method of multiplying Treg cells in vitro.

FIELD OF THE INVENTION

The present invention concerns therapeutic vaccine for treatment ofdiabetes type 1 in children, application of the cell sorter to producetherapeutic vaccine for treatment of diabetes type 1, and the method ofmultiplying Treg cells in vitro to produce therapeutic vaccine fortreatment of diabetes type 1.

PRIOR ART

Diabetes type 1 (DM1A) is a genetically linked disease, however allresearchers agree that direct damage to β cells in the pancreas is dueto autoimmune reaction. Speaking in favour thereof are both the presenceof antibodies towards β cell antigens, and lymphocytic infiltration tothe islets of Langerhans, or the so-called insulitis, accompanied byincreased β cell apoptosis.

The regulatory T-lymphocytes (Treg) form a specific population in theimmune system. Although accounting for less than 1% of the leucocytes inthe peripheral blood, they regulate the immune response so that swiftelimination of harmful pathogens is possible while our own tissuesremain protected. This is because Treg cells do not block other cells ofthe immune system when foreign pathogens are attacked, but provestrongly inhibiting when the immune system begins to destroy our owntissues and organs. Therefore by analogy, the immunosuppressive actionof Treg cells sometimes earns them the name of the “intelligentsteroids”.

Reduced numbers of Treg cells in the organism are associated withtransplant failures and incidence of allergic and autoimmune diseases.One of the diseases characterised by numerical deficiency of Treg cells,is diabetes type 1 where autoimmune attack destroys the patient'spancreas.

Known from the international publication WO 2004/110373 is a vaccinecomposition that comprises modified insulin B chain components suitablefor use as immunogenic agents for treatment and prevention of type 1diabetes.

Known from publication WO 2012/001099, on the other hand, is vaccinecontaining at least one enterovirus selected from the group including:Coxsackie viruses CAV4, CAV5, CAVE, and echovirus E18, or its component.The description states that the listed enteroviruses are linked todiabetes type 1, which opens new therapeutic and diagnosticpossibilities.

Similarly, the description of WO 2012/001100 discloses vaccinecomprising e.g. Coxsackie B virus CBV1 to prevent or treat diabetestype 1. It has been found that the virus is strongly associated with therisk of contracting diabetes type 1.

The above publications disclose vaccines intended for treatment ofdiabetes type 1, nevertheless they are different than the vaccine beingthe gist of this invention.

In order to increase the effectiveness of treating diabetes type 1 inchildren it is necessary to search for more effective and successfulmethods of treating the disease.

GIST OF THE INVENTION

Unexpectedly, it has been found that the new therapeutic vaccine fortreatment of diabetes type 1 prevents the disease effectively.Administration of the vaccine according to this invention to patientsresults in an increase in the primary marker of the pancreas function,i.e. the C-peptide level. In addition, the sorter employed wasoriginally dedicated to cell therapies, which enhances its safety.

The gist of the invention consists in the therapeutic vaccine fortreatment of diabetes type 1 in children, which contains:

-   -   Treg cells CD3(+)CD4(+)CD25(high)CD127(−).

The gist of this invention further consists in employing the cell sorterto produce the therapeutic vaccine for treatment of diabetes type 1,where the cells are sorted to isolate Treg cells using the algorithmsorting out the following phenotype:

-   -   CD3(+)CD4(+)CD25(high)CD127(−)doublet(−)lineage(−)dead(−).

The gist of this invention also consists in the method of multiplyingTreg cells in vitro to produce therapeutic vaccine for treatment ofdiabetes type 1, where:

-   -   lymphocytes T CD4+ are isolated by the immunomagnetic method and        marked with monoclonal antibodies,    -   the sorter-isolated Treg cells are multiplied in the CellGro or        X-VIVO medium supplemented with autological inactivated serum        and interleukin-2,    -   the culture is supplemented with artificial antigen-presenting        cells in the 1:1 proportion.

Selected for the marking are the following monoclonal antibodies:anti-CD3, anti-CD4, anti-CD8, anti-CD19, anti-CD14, anti-CD16,anti-CD25, and anti-CD127.

The monoclonal antibodies CD3, CD4, CD8, CD19, CD14, CD16, CD25, andCD127 recognise the antigens, and are conjugated with fluorescent dyes.

The antigen-presenting artificial cells are magnetic beads coated withanti-CD3 and anti-CD28 antibodies.

The figures:

FIG. 1—presents the level of Treg cells CD3+CD4+CD25highCD127-FoxP3+ inchildren suffering from diabetes type 1, subject to the Treg celltherapy (n=10) over four months' observation. The value at point “−10days” represents the day the blood was drawn for Treg cell isolation.The grey columns present the results obtained for children notadministered the Treg lymphocyte infusion (control group; n=10). Thevalues are given at their median, minimum, and the maximum levels. Thestatistically significant values (p<0.05) are marked with “*”.

FIG. 2—presents the C-peptide, the daily insulin dose/kg BW (DDI/kg),and the HbA1C in the tested children with diabetes type 1, subject tothe Treg cells therapy (n=10) over the four months' observation. Theresults for the patients not administered the cell preparation (controlgroup; n=10) are presented in grey columns. The values are given attheir median, minimum, and the maximum levels, and the statisticallysignificant values (p<0.05) are marked with “*”.

The invention is illustrated with the following embodiment, which isexemplary, i.e. not limiting in nature.

EXEMPLARY EMBODIMENT

250 ml of peripheral blood was sampled from each patient with theassistance from an anaesthesiologist. In the case of children whose bodyweight was less than 50 kg the sampled blood volume accounted for 0.5%of the body weight (BW). This concerns patients under the age of 18.

The collected blood was processed at the Regional Centre of BloodDonation and Treatment in Gdansk to extract the buffy coat and serum.Isolated from the buffy coat were peripheral blood mononuclear cells(PBMC) through centrifuging in the Ficoll/Uropolin concentrationgradient. Lymphocytes T CD4+ were then separated by the immunomagneticmethod (separation purity: 96-99%) using the CD4+T enrichment kit andmarked with the following monoclonal antibodies (mAb): anti-CD3,anti-CD4, anti-CD8, anti-CD19, anti-CD14, anti-CD16, anti-CD25, andanti-CD127 (5 ul mAb/10⁶ cells). Among the listed antibodies those whichrecognize antigens CD14, CD16, CD19, and CD8 were conjugated with thesame dye. The purpose of that dying scheme was to exclude the cellspositive with respect to the listed antigens (i.e. monocytes, NK cells,lymphocytes B and cytotoxic T lymphocytes) without the need to introduceadditional fluorochromes, which reduces the undesirable phenomenon offluorescent spectra overlapping. Then, the cells were sorted to separateTregs using a sorting cytometer to the algorithm sorting the followingphenotype: CD3(+)CD4(+)CD25(high)CD127(−)doublet(−)lineage(−)dead(−).

The adopted exemplary dying scheme (antibody; dye name acronym, fullname of the dye)

-   -   antiCD127 FITC (Fluorescein isothiocyanate)    -   antiCD25 PE (phycoerythrin)    -   antiCD16 PerCP (Peridinin Chlorophyll Protein Complex)    -   antiCD19 PerCP (Peridinin Chlorophyll Protein Complex)    -   antiCD8 PerCP (Peridinin Chlorophyll Protein Complex)    -   antiCD14 PerCP (Peridinin Chlorophyll Protein Complex)    -   antiCD4 APC (allophycocyanin)    -   antiCD3 Pacific Blue/Pacific Blue        or equivalents evoked to emit fluorescent light in similar        spectrum ranges.

The purity of the thus isolated Treg cells was ˜100% [median(min-max):98%(97-99)]. An important modification compared to our earlier procedureconsisted in applying the Influx cell sorter designed in accordance withthe good manufacturing practices (GMP). The sorter is fitted with areplaceable sample flow line, which eliminates the risk of samplecross-contamination among the patients. Moreover, applied was theCellGro medium meeting the GMP standards or X-VIVO. The medium wassupplemented with autological inactivated serum (10%) and interleukin-2(1000 U/ml). Introduced into the culture were the so-calledantigen-presenting artificial cells [magnetic beads coated with anti-CD3and anti-CD28 antibodies in the 1:1 proportion. The cells werecultivated until the appropriate number was attained, though no longerthan for 2 weeks [median(min-max): 10 days (7-12)].

The above indicated modifications allowed the attainment ofsubstantially improved stability and quality of the cultured Treg cellsin the final product. The actual application of the preparation intherapy was conditional on satisfaction of the following criteria:factor FoxP3 expression above 90% [median(min-max)=93%(90-97)], positiveresult of the IFNγ production inhibition test, and negative results ofmicrobiological tests—no genetic material of the HBV, HCV, or HIVviruses, and no bacterial contamination in the culture supernatants.Before infusion, the cells were washed with PBS, the magnetic beadsremoved, and administered in slow intravenous injection in 250 ml 0.9%NaCl under supervision of the anaesthesiologist within 1 h after theproduct release. The therapeutic dose was 20×10⁶/kg BW (n=6), or10×10⁶/kg BW (n=4; whenever no higher number of cells had been achievedupon cultivation for 2 weeks), or 30×10⁶/kg body weight. The controlgroup was made up of patients who met all above-listed criteria ofinclusion in the test, except for appropriate venous access, hence werenot treated with the Treg vaccine. The test was not randomised, nor wasthere a blank sample introduced, and the children of the control groupwere not subject to any medical intervention related to the pendingtests (blood sampling, simulated transfusion, or the like). Table 1provides the characteristics of the tested groups. The test endpointswere as follows: the fasting C-peptide level, the HbA1c concentration,the insulin requirement, especially the daily dose (DDI)=0.5 UI/kg BWadopted as the remission indicator. The test was conducted in accordancewith the procedure approved by the Independent Research BioethicsCommittee at the Medical University of Gdansk (NKEBN/8/2010). A writtenconsent to the above procedure was obtained from each patient and theparents.

None of the patients was observed to develop any serious infections,episodes of acute hyper-/hypoglycaemia, or any other undesirable sideeffects of the Tregs vaccine at any time over the test period. In caseof one patient the Treg cell infusion date coincided with flu diagnoseda day after the Treg cells had been administered.

Beginning on the infusion date and continuously afterwards the recordedTreg lymphocyte per cent level in the peripheral blood was significantlyincreased (Wilcoxon test, p=0.04) (FIG. 1).

Two weeks after the Treg cell infusion all patients subject to thetherapy were observed to demonstrate substantially reduced demand forexogenous insulin and a reduced HbA1c level (FIG. 2).

The first significant differences between the test group and thepatients of the control group were observed six months after formulationof the diabetes diagnosis (5-6 months after the Treg cell infusion). Thetreated patients continued in the remission phase [DDImedian(min-max)=0.24 UI/kg BW (0-0.55)], whereas the control groupexperienced the end of remission [DDI median(min-max)=0.55 UI/kg BW(0.43-0.69)] (Mann-Whitney U test, p=0.03). In addition, the childrentreated with Treg cells proved to have a significantly higher level ofC-peptide [median(min-max): 0.65 ng/ml (0.46-2.11) vs. 0.40 ng/ml(0.15-0.54)] (Mann-Whitney U test, p=0.04) (FIG. 3). No differences withrespect to therapy effectiveness were observed in the patients who hadbeen administered Treg cells dosed at 20×10⁶/kg BW or 10×10⁶/kg BW.Therefore, all results of the test group are presented en block.

LITERATURE

-   1. Marek N, Krzystyniak A, Ergenc I, Cochet O, Misawa R, Wang L J,    Go    çb K, Wang X, Kilimnik G, Hara M, Kizilel S, Trzonkowski P, Millis J    M, Witkowski P. Coating human pancreatic islets with    CD4(+)CD25(high)CD127(−) regulatory T cells as a novel approach for    the local immunoprotection. Ann Surg. 2011; 254(3):512-8; discussion    518-9.-   2. Marek N, Bieniaszewska M, Krzystyniak A, Juscinska J, Mysliwska    J, Witkowski P, Hellmann A, Trzonkowski P. The time is crucial for    exvivo expansion of T regulatory cells for therapy. Cell Transplant.    2011 (20):1747-1758;-   3. Trzonkowski P. All roads lead to T regulatory cells.    Transplantation. 2011; 91(2):150-1.-   4. Trzonkowski P, Bieniaszewska M, Juścińska J, Dobyszuk A,    Krzystyniak A, Marek N, Myśliwska J, Hellmann A. First-in-man    clinical results of the treatment of patients with graft versus host    disease with human ex vivo expanded CD4+CD25+CD127− T regulatory    cells. Clin Immunol. 2009; 133(1):22-6.-   5. Trzonkowski P, Szaryńska M, Myśliwska J, My{grave over    (s)}liwski A. Ex vivo expansion of CD4(+)CD25(+) T regulatory cells    for immunosuppressive therapy. Cytometry A. 2009; 75(3):175-88.-   6. Ryba M, Marek N, Hak    , Rybarczyk-Kapturska K, Myśliwiec M, Trzonkowski P, Myśliwska J.    Anti-TNF rescue CD4+Foxp3+ regulatory T cells in patients with type    1 diabetes from effects mediated by TNF. Cytokine. 2011;    55(3):353-61.-   7. Trzonkowski P, Szmit E, Myśliwska J, Myśliwski A. CD4+CD25+ T    regulatory cells inhibit cytotoxic activity of CTL and NK cells in    humans-impact of immunosenescence. Clin Immunol. 2006;    119(3):307-16.-   8. Trzonkowski P, Szmit E, My{grave over (s)}liwska J, Dobyszuk A,    Myśliwski A. CD4+CD25+ T regulatory cells inhibit cytotoxic activity    of T CD8+ and NK lymphocytes in the direct cell-to-cell interaction.    Clin Immunol. 2004; 112(3):258-67.-   9. Trzonkowski P, Zaucha J M, Mysliwska J, Balon J, Szmit E,    Halaburda K, Bieniaszewska M, Mlotkowska M, Hellmann A, Mysliwski A.    Differences in kinetics of donor lymphoid cells in response to G-CSF    administration may affect the incidence and severity of acute GvHD    in respective HLA-identical sibling recipients. Med Oncol. 2004;    21(1):81-94.-   10. Go    çb K, Krzystyniak A, Marek-Trzonkowska N, Misawa R, Wang L J, Wang    X, Cochet O, Tibudan M, Langa P, Millis J M, Trzonkowski P.,    Witkowski P. Impact of culture medium on CD4+ CD25highCD127lo/neg    Treg expansion for the purpose of clinical application. Int    Immunopharmacol. 2013. doi:pii: S1567-5769(13)00058-1.    10.1016/j.intimp.2013.02.016

1. Therapeutic vaccine for treatment of diabetes type 1 in childrencharacterised in that it contains: Treg cellsCD3(+)CD4(+)CD25(high)CD127(−)
 2. Application of the cell sorter toproduce the vaccine defined in claim 1, characterised in that the cellsare sorted to isolate Treg cells using the algorithm sorting thefollowing phenotype:CD3(+)CD4(+)CD25(high)CD127(−)doublet(−)lineage(−)dead(−).
 3. The methodof multiplying Treg cells in vitro to produce the vaccine defined inclaim 1, characterised in that: lymphocytes T CD4+ are isolated by theimmunomagnetic method and marked with monoclonal antibodies, thesorter-isolated Treg cells are multiplied in the CellGro CellGro orX-VIVO medium supplemented with autological inactivate serum andinterleukin-2, the culture is added artificial antigen-presenting cellsin the 1:1 proportion.
 4. The method according to claim 3, characterisedin that selected for the marking are the following monoclonalantibodies: anti-CD3, anti-CD4, anti-CD8, anti-CD19, anti-CD14,anti-CD16, anti-CD25, and anti-CD127.
 5. The method according to claim3, characterised in that the monoclonal antibodies CD3, CD4, CD8, CD19,CD14, CD16, CD25, and CD127 recognise the antigens, and are conjugatedwith fluorescent dyes.
 6. The method according to claim 3, characterisedin that the antigen-presenting artificial cells are magnetic beadscoated with anti-CD3 and anti-CD28 antibodies.